What is the capacitor?

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 The Capacitor.         A capacitor is formed when two conductors, usually of aluminium, are separated by an insulator sus as paper ect. For use in motors the strips are rolled together into a compact unit and placed into a sealed metal or plastic container. This may be either cylinderical or rectangular in shape and may be mounted on, in, or away from the motor. Two terminals or leads are provied for connection. The name capacitor is descriptive of the operation of the device. The capacitor acts essentially as a storage units that is,has capacity to store electricity and provides a leading current to the auxiliary or starting winding. All capacitors have this quality and all are electrically the same;they differ only in mechanical construction.     THE OIL-FILLED CAPACITOR                 This capacitor is used mainly in the permanent-split capacitor motor and for the two-value capacitor motor. The capacitor use an oil-impregnated paper as the dielectric and are permanently conne
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Auto- transformer starter

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     The starter of this type are used upto 25H.P. motors. This type of starter has autos transformer from which many tapping are taken out which give different voltages by which a big motor can be be supplied by low voltage. While in the in the star delta starter only 1/√3 times the full voltage can be given to the motor. The torque also varies with the voltage.
       This starter also has overload relay, no volt coil and "OFF" switch.
      In this starter the overload coil works on the magnetic effect I.e. when the current in the flows more than the normal, overload relay opens overload switch.

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